Problem: A bag contains $7$ red marbles, $9$ green marbles, and $6$ blue marbles. If a marble is randomly chosen, what is the probability that it is not green?
Explanation: There are $7 + 9 + 6 = 22$ marbles in the bag. There are $9$ green marbles. That means $22 - 9 = 13$ are not green. The probability is $ \frac{13}{22}$.